Charge and Spin Thermoelectric Transport in Benzene-Based Molecular Nano-Junctions: A Quantum Many-Body Study

Abstract

Within the Coulomb blockade regime, our study delves into the charge, spin, and thermoelectric transport characteristics in a benzene-based molecular nano-junction using the Pauli master equation and linear response theory. The charge- and spin-transport studies show strong negative differential conductance features in the current-voltage ($I-V$) characteristics for the ortho and meta connections of electrodes on either side. Contrarily, the para-connection displays Coulomb staircase behavior. Exploring spin current behavior in the presence of spin-polarized electrodes or external Zeeman field, we establish a methodology that facilitates precise control over the specific spin flow. Various charge and spin thermoelectric transport coefficients have been studied with varying chemical potentials. We focus on spin-polarized-conductance, the Seebeck coefficient, and the figure of merit. By adjusting electrode polarization or employing an external magnetic field, we achieve an impressive peak value for the spin thermoelectric figure of merit, approximately 4.10. This outcome underscores the strategic value of harnessing both spin-polarized electrodes and external magnetic fields within the domain of spin caloritronics.

40 pages, 10 figures

References in corpus (17)

• Optimal thermoelectric figure of merit of a molecular junction
• Violation of the Wiedemann-Franz Law in a Single-Electron Transistor
• Electron- and phonon transport in silicon nanowires: an atomistic approach to thermoelectric properties
• Thermo-spin effects in a quantum dot connected to ferromagnetic leads
• Engineering Enhanced Thermoelectric Properties in Zigzag Graphene Nanoribbons
• Many-body theory of electronic transport in single-molecule heterojunctions
• Quantum Dot as a Spin--Current Diode
• A benzene interference single-electron transistor
• Multiterminal single-molecule--graphene-nanoribbon thermoelectric devices with gate-voltage tunable figure of merit ZT
• Spin effects in transport through single-molecule magnets in the sequential and cotunneling regimes
• Symmetry fingerprints of a benzene single-electron transistor
• Quantum-fluctuation effects on the thermopower of a single-electron transistor
• Controlling Spin Qubits in Quantum Dots
• Thermal bridging of graphene nanosheets via covalent molecular junctions. a Non-Equilibrium Green Functions Density Functional Tight-Binding study
• Spin-polarized currents in double and triple quantum dots driven by ac magnetic fields
• Spin-Seebeck effect and spin polarization in a multiple quantum dot molecule
• Tunable Charge and Spin Seebeck Effects in Magnetic Molecular Junctions

Cited by in corpus (2)

• Thermoelectric performance of quantum dots embedded in an Aharonov-Bohm ring: a Pauli master equation approach
• Enhanced thermopower in two-dimensional ruthenium dichalcogenides $Ru{X}_2$ (X = S, Se): a first-principles study